1. Field of the Invention
This invention relates to an apparatus and method that notifies roadside work crews or other persons located near a roadway or highway to the approach of on-coming traffic that could collide with said persons thereby representing a significant risk of bodily harm to them. Specifically, the invention uses a control unit, a special graphical user interface coupled to the control unit, a speed and distance detection device coupled to the control unit, and an alert unit coupled to the control unit, where the invention can be programmed in the field by the crew to signal of on-coming vehicles with certain speed and distance characteristics to provide crews with the necessary reaction times to avoid injury. Reaction time is the amount of time before the on-coming vehicle will reach the crews or other designated location in the work zone. The control unit receives instructions from the graphical user interface and special software operated by a processor where the control unit in turn controls the other invention elements. The control unit signals the alert unit to start an alarm sequence when vehicles are within the specified threshold of characteristics.
2. Description of Related Art
There have been other roadside alert systems. The prior art that appears to be the closest in kind to this invention may be U.S. Pat. No. 5,760,686 by Toman. Toman discloses a system with an optical detection array for detecting physical entry of a hazardous vehicle when it crosses a leg of the array thereby entering a predefined work zone. The detection array is coupled to an optical alert device. Toman teaches an optical signaling alert and opposes an audible alert with rationale that work crews would not be able to hear an audible alarm due to work noise, where an optical alarm is otherwise more effective than an audible alarm. Toman also discloses an embodiment with a radar operated excessive speed detector that is preset to trigger an alarm when a vehicle exceeds the preset speed threshold. The detector would then signal the optical alarm to initiate when a vehicle surpasses the preset speed threshold.
The instant invention also discloses a type of radar operated excessive speed detector. In this case, a speed and distance detection device communicates with a control module, where the control module may signal an alarm based on data received from the speed and distance detection device. However, the speed and distance detection device of this invention does not simply detect speed; it is a combination speed and distance detector. The combination detector is required to yield a main aspect of this invention, which is the ability to trigger an alarm sequence according to reaction time and not simply according to speed of the hazardous vehicle.
The idea is that work crews can program the alarm to sound according the specific reaction times determined by the particular time required to notice a hazardous vehicle and then complete evasive measures to avoid being struck by the vehicle. Required reaction times may vary according the specific activity being conducted by the work crews. Thus, if a crew is performing a task that allows personnel to keep a fairly watchful eye on the roadway, such as flagging or surveying, the crew would require a relatively short reaction time, perhaps only 4 seconds, to take effective evasive maneuvers to avoid injury. On the other hand, if the crew is performing more involved roadwork work, such as repaving or repairing, that affords little attention to on-coming traffic, the crew would require much more reaction time, perhaps 12 seconds, to complete evasive maneuvers, such as dropping the shovel and exiting the work area, to avoid injury. We believe this invention is the first roadside alarm device that triggers according to road crew personnel reaction time and also allows the crews to program desired reaction times for the alert in a very user friendly manner.